Gallbladder Ultrasound: Did You See That Stone in the Neck?

There’s something deeply satisfying about spotting that tiny, shadow-casting culprit tucked in the neck of the gallbladder. Every sonographer knows the moment, you freeze the image, zoom in and there it is, the stone that explains it all.

Gallbladder ultrasound may seem straightforward, but it’s full of traps and nuances that separate the beginner from the skilled eye. Whether you’re a student still learning to navigate acoustic windows or a practicing sonographer fine-tuning your technique, understanding what to look for and what not to miss is key.

The Gallbladder: Small Organ, Big Clues

The gallbladder sits quietly under the right lobe of the liver, waiting to give up its secrets. It stores bile, concentrates it, and helps digest fat until something goes wrong. When bile stagnates, stones form. Those stones can block the cystic duct, irritate the wall, and trigger inflammation giving the classic presentation of acute cholecystitis.

But here’s the catch: not every painful gallbladder tells the same story, and not every shadow is what it seems.

What Every Sonographer Should Look For

So, let’s break it down, this is what should always be on our radar:

• Gallstones or sludge: Look for mobile, echogenic foci with posterior shadowing. If it’s sludge, it will layer and move slowly with patient position.

• Gallbladder wall: Normal thickness ≤3 mm. Thickening can occur from infection, heart failure, or hypoalbuminemia so always interpret in context. Not all wall thickening is cholecystitis.

• Pericholecystic fluid: A sign of inflammation or perforation risk.

• Sonographic Murphy sign: Gently press over the gallbladder, focal tenderness at that exact site is a hallmark of acute cholecystitis.

• CBD (common bile duct): Dilatation (>6 mm) may indicate obstruction.

The Stone in the Neck: Why It Matters

That small shadow in the gallbladder neck is often the troublemaker. It can obstruct the cystic duct without causing full distension, leading to subtle or intermittent symptoms.Always take your time to sweep through the neck region in both longitudinal and transverse planes. Stones can hide — especially in partially contracted gallbladders.

Oh and don’t forget to change the patient’s position, left lateral decubitus or upright to watch if the stone rolls or stays fixed. If it’s stuck in the neck and immobile, you might be looking at acute or chronic cholecystitis in the making.

Common Pitfalls:

Even seasoned sonographers can get tripped up.Here’s what to watch out for:

• Bowel gas mimicking the gallbladder so check for peristalsis.

• Sludge balls mistaken for stones, they don’t shadow.

• Over-gained images too much gain can wash out subtle wall changes.

• Calling every thick wall “cholecystitis” — remember systemic causes.

Pro Tip from the Field

If you suspect cholecystitis but the gallbladder looks borderline, look at vascularity by using color Doppler. Hyperemia of the wall can confirm inflammation even before fluid or marked distension appears.

Elevate Your Technique

At SonoSavvy Institute, we teach more than protocols — we teach sonographers how to think while they scan. Our abdominal ultrasound training programs focus on the practical, hands-on scanning skills that help you:

• Identify subtle pathology confidently

• Optimize your image for diagnosis

• Recognize artifacts vs. true disease

• Communicate findings like a pro

👉 Book your private abdominal ultrasound training session and transform your scanning confidence.